Marine Weather and Tides
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|Sunrise 6:46AM||Sunset 7:00PM||Friday September 21, 2018 11:42 AM EDT (15:42 UTC)||Moonrise 4:35PM||Moonset 2:10AM||Illumination 89%|
7 Day Forecast for Marine Location Near Portland , PAHourly EDIT Help
Area Discussion for - Philadelphia/Mount Holly, PA  (on/off)  Help NOTE: mouseover dotted underlined text for definition
|Fxus61 kphi 211307|
area forecast discussion
national weather service mount holly nj
907 am edt Fri sep 21 2018
A cold front will cross the region tonight into Saturday, stalling
to the south of the region through Monday. The boundary then lifts
north as a warm front on Tuesday, followed by a cold front on
Wednesday. A brief return to high pressure is expected for the end
of the week. High pressure returns for Thursday.
Near term until 6 pm this evening
High pressure off the canadian maritimes will continue to bring an
onshore component to the surface flow this morning, though it will
be gradually veering to the south and southwest with time. Until
then, expect a low-cloud deck to persist, especially away from the
coast (where upslope effects contribute to the associated lift).
Meanwhile, a strong vort MAX approaching the great lakes and ontario
will allow a strong surface cyclone to progress rapidly east-
northeast into quebec late this afternoon. A strong cold front will
extend south-southwest into the lower great lakes and ohio valley by
21z. Large-scale lift downstream of the vort MAX combined with
boundary-layer instability in the warm sector to our west will allow
the front to develop convection readily by afternoon. A squall line
should mature fairly quickly and move into western new york and
pennsylvania late this afternoon. The front will remain well west of
us through this time, and the threat of severe weather in our area
is minimal today as a result.
This morning, a predecessor vort MAX will move through new york and
new england, with subtle lift in advance of the perturbation. This
may generate some showers (as per the 00z NAM nest; the hrrr is
generally less aggressive) in the poconos, far northwest new jersey,
and the lehigh valley. Maintained some pops here through midday,
though any rainfall would be quite light. As the vort MAX progresses
eastward this afternoon, this threat will wane, and pops are
generally unmentionable during this time frame.
Temperatures today are a real challenge, and it will be tied closely
to the persistence of the cloud cover. Statistical guidance has
trended downward considerably over the past 48 hours, with consensus
in the mid to upper 70s in the urban corridor. I went on the higher
side of consensus (but only by about a degree or two), as the bias
has been for statistical guidance to be too stubborn with the
persistence depth of cloudiness in recent days.
Short term 6 pm this evening through 6 am Saturday
Main challenge tonight is forecasting the longevity of the squall
line to our west.
As the cold front sweeps eastward into the northeastern mid-
atlantic, nocturnal cooling will rapidly diminish any boundary-layer
instability downstream of the squall line. Expect a fairly rapid
decrease in strength to this convection (especially as the storms
will also begin to move away from the cooler midlevels in proximity
to the attendant vort max). The NAM nest suggests convection may
survive into the poconos before diminishing rapidly in the lehigh
valley and northern new jersey between 03z and 08z. I did increase
pops in these areas (including some likely pops this evening) and
expanded mentionable pops to the urban corridor, but by this point,
any remaining showers look sparse weak. Cannot rule out a strong
gust even in the absence of thunder given the strong flow aloft, but
the stable and stabilizing boundary layer will likely preclude
a damaging wind threat for our cwa. The SPC has shifted the
marginal risk of severe storms primarily out of our CWA (except
the poconos), which is quite reasonable given the 00z hi-res
simulations and forecast soundings overnight.
Other concern is timing the associated cold front, which will be
moving into the area fairly quickly late tonight. Sped up the timing
a little bit based on latest guidance and a general slow bias models
have in these regimes. May even see some clearing (with shift to
northwest winds) in the northwest CWA by daybreak.
Forecast lows are a statistical guidance continuity blend, with
readings in the 50s in the poconos and the 60s elsewhere except
perhaps the immediate coast. The forecast is somewhat low-confidence
owing to potential effects from precipitation and cold-frontal
Long term Saturday through Thursday
Saturday... The cold front will sag south of the region early
Saturday, becoming nearly stationary just south of our forecast
area. Generally expecting some cooler and drier weather across the
region on Saturday as northwest flow is across the region.
Saturday night through Sunday... The flow starts to turn more to the
north northeast by Sunday morning. High pressure will build to the
north of the region with the surface front off to our south. We kind
of get squeezed between the two systems and a stream of mid level
shortwaves move through our area on Sunday. While it won't be an
overly wet day across the region, we will see cloud cover increase
and a chance for showers will be present, especially across delmarva
and southern new jersey.
Monday through Tuesday... The high pressure to our north will remain
in place through at least Monday before starting to shift offshore
on Tuesday. The front to the south will try to push northward as a
warm front but that will be blocked by the strength of the high to
the north, suppressing much, if any, northward progress. The front
starts to push northward again late Monday into Tuesday as the
departing high removes the blocking across our area. The warm front
will lift through our area on Tuesday bringing increased chances for
showers and thunderstorms. With a couple of shortwaves rotating
through, we should have enough lift to support convection continuing
through Tuesday night, although it may be scattered or isolated.
Wednesday... A brief break in the weather may occur ahead of a cold
front arriving on Wednesday. The front will cross the region and
again we will see an increased chance for showers and thunderstorms
across the region. Southerly flow ahead of the front will increase
moisture across the region and pwats will start to rise near 2|
inches, leading to efficient rainfall within any shower or storm
that develops. Although it looks like Wednesday will be a fairly
cloudy day, any breaks in the clouds will help increase surface
instability and help in the development of thunderstorms. As the
front pushes to the east, showers and thunderstorms will decrease in
coverage from west to east. While some lingering showers may remain
into the overnight, we should start to see some drying out occur in
the developing northwest flow.
Thursday... The cold front pushes well south of our area, stalling
closer to the carolinas. High pressure will build across the
northern mid-atlantic and into new england on Thursday. As the high
slides across to our north, we should see the northwest flow turn
more to the north or northeast Thursday. If the high can build a
little further south, we may be able to squeeze out a dry day across
the region. However, with easterly flow developing, we could see
some scattered showers develop. Therefore, continue to mention a
chance for some showers in the forecast.
Aviation 13z Friday through Tuesday
The following discussion is for kphl, kpne, kttn, kabe, krdg, kilg,
kmiv, kacy and surrounding areas.
Today... Continued slow improvement with CIGS toVFR, even at
rdg abe. Southeast winds around 10 kts in the late morning
becoming south to southwest in the afternoon. Moderate
Tonight... CIGS may lower to near or even slightly below MVFR as
a cold front approaches. Cannot rule out a shower after
midnight, especially at rdg abe, but chances are too low for taf
inclusion at this point. Southwest winds around below 10 kts
becoming more westerly late. Low confidence.
Saturday... MainlyVFR conditions expected. Northwest to north winds
around 5 to 10 knot becoming north around 5 knots overnight. MVFR
conditions possible Saturday night, mainly at kmiv kacy.
Sunday... MainlyVFR conditions expected. Conditions may drop to
MVFR ifr at times in showers and thunderstorms, mainly south of
kphl. Northeast winds around 5 to 10 knots.
Monday... MainlyVFR conditions expected. Conditions may drop to
MVFR ifr at times in showers and thunderstorms. East winds around 10
to 15 knots with gusts around 20 knots. Higher gusts possible at
Monday night through Tuesday... MVFR or lower conditions in showers
and thunderstorms. East winds around 10 to 15 knots becoming
southeast on Tuesday. Gusts around 20 knots possible.
Onshore flow this morning will veer to southerly during the
afternoon and increase. Advisory conditions are not expected during
the daytime hours, but gusts will approach or possibly even exceed
slightly 20 knots by late afternoon. As winds continue to veer to
southwesterly tonight, gusts should exceed 25 knots on all atlantic
waters through the overnight hours, gradually diminishing by
daybreak Saturday. Seas may approach five feet as well, though
models are trending a little bit lower.
Made no changes to the small craft advisory tonight. Gusts may
approach advisory levels on delaware bay, so will need to monitor
latest model output to determine if an advisory will be required
here as well. For now, conditions look too marginal.
Saturday through Sunday... West northwest winds on Saturday will turn
to the north and then northeast for late Saturday night through
Sunday. Seas will be around 2 to 4 feet.
Monday through Tuesday... Tightening pressure gradient will allow for
winds to start gusting around 25 to 30 knots on Monday and
continuing through mid-day Tuesday. Seas will rise and exceed 5 feet
on Monday, possible by late Sunday night in the southern waters. A
small craft advisory will likely be needed.
there is a moderate risk of rip currents today, as medium-to-
long period easterly swell continues with waves in the surf zone
of 3 to 5 feet.
Tides coastal flooding
High tide on chesapeake bay has passed, and water levels will
continue to recede. The coastal flood advisory has been
There is a chance for spotty minor coastal flooding along
chesapeake bay with the high tide Saturday morning.
Phi watches warnings advisories
Marine... Small craft advisory from 6 pm this evening to 6 am edt
Saturday for anz450>455.
near term... Cms mps
short term... Cms
long term... Meola
aviation... Cms meola mps
marine... Cms meola mps
tides coastal flooding... Mps
Weather Reporting StationsEDIT (on/off)  Help NOTE: Click on distance to see the station location on a map
|Stations||Dist||Age||Wind||Air Temp||Water Temp||Waves||Pressure||DewPt|
|BGNN4 - 8519483 - Bergen Point West Reach, NJ||53 mi||42 min||70°F||74°F||1023.5 hPa (-0.9)|
|NBLP1 - 8548989 - Newbold, PA||56 mi||42 min||S 5.1 G 8.9||70°F||69°F||1023.9 hPa (-1.1)|
|ROBN4 - 8530973 - Robins Reef, NJ||57 mi||42 min||S 12 G 15||69°F||1024.2 hPa (-0.8)|
Wind History for Bergen Point West Reach, NY(wind in knots) EDIT (on/off)  Help
Airport ReportsEDIT (on/off)  Help Click EDIT to display multiple airports
|Andover, Aeroflex-Andover Airport, NJ||20 mi||1.8 hrs||Var 5||mi||65°F||60°F||84%||1023.6 hPa|
|Mount Pocono, Pocono Mountains Municipal Airport, PA||22 mi||1.8 hrs||S 7||10.00 mi||Overcast||58°F||57°F||100%||1023.9 hPa|
Wind History from 12N (wind in knots)
|1 day ago||N||Calm||Calm||NW||Calm||Calm||Calm||Calm||Calm||Calm||Calm||Calm||Calm||Calm||NE||NE||Calm||S||Calm||Calm||SE|
|2 days ago||Calm||N||N||Calm||Calm||Calm||Calm||Calm||Calm||Calm||Calm||Calm||Calm||Calm||Calm||Calm||Calm||Calm||Calm||NE|
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Wind Forecast for Philadelphia/Mount Holly, PA (11,2,3,4)(on/off)  Help
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